A fistula is generally a passageway formed between two internal organs. Forming a fistula between two blood vessels can have one or more beneficial functions. For example, the formation of a fistula between an artery and a vein may provide access to the vasculature for hemodialysis patients. Specifically, forming a fistula between an artery and a vein allows blood to flow quickly between the vessels while bypassing the capillaries. Needles, catheters, or other cannulas may then be inserted into the blood vessels near the fistula to draw blood from the circulatory system, pass it through a dialysis machine, and return it to the body. The quickened flow provided by the fistula may provide for effective hemodialysis. Generally, fistula formation requires the surgical dissection of a target vein, transecting and moving the vein for surgical anastomosis to the artery. These fistulas typically have a primary failure rate (failure before the patient receives dialysis) of about 30-60%, and take between 5 and 12 months before the fistula is usable for dialysis. It may be useful to find improved ways to form a fistula between two blood vessels.